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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...doesn't have to sort the output, and GROUP BY by default does. However, in MySQL even a DISTINCT+ORDER BY might still be faster than a GROUP BY due to the extra hints for the optimizer as explained by SquareCog.
– rustyx
Jan 25 '15 at 15:03
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how to customize `show processlist` in mysql?
...any way you like.
The INFORMATION_SCHEMA.PROCESSLIST table was added in MySQL 5.1.7. You can find out which version you're using with:
SELECT VERSION()
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Rank function in MySQL
...NSI standard SQL query for my requirement. Please help me to convert it to MySQL .
11 Answers
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MySQL select where column is not empty
In MySQL, can I select columns only where something exists?
13 Answers
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MySQL: Set user variable from result of query
Is it possible to set an user variable based on the result of a query in MySQL?
4 Answers
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Change limit for “Mysql Row size too large”
... You may want to take a look at this article which explains a lot
about MySQL row sizes. It's important to note that even if you use
TEXT or BLOB fields, your row size could still be over 8K (limit for
InnoDB) because it stores the first 768 bytes for each field inline in
the page.
The...
SQL Server equivalent to MySQL enum data type?
Does SQL Server 2008 have a a data-type like MySQL's enum ?
5 Answers
5
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“21天教你学会C++” - 创意 - 清泛网 - 专注C/C++及内核技术
...法（如果你已经会一门类似的语言），但你无法学到多少如何运用这些语法。简而言之，如果你是，比如说一个Basic程序员，你可以学会用C++语法写出Basic风格的程序，但你学不到C++真正的优点（和缺点）。那关键在哪里？Alan Per...
Convert Unix timestamp into human readable date using MySQL
Is there a MySQL function which can be used to convert a Unix timestamp into a human readable date? I have one field where I save Unix times and now I want to add another field for human readable dates.
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How to DROP multiple columns with a single ALTER TABLE statement in SQL Server?
...DROP { [ CONSTRAINT ] constraint_name | COLUMN column } [ ,...n ]
For MySQL:
ALTER TABLE TableName
DROP COLUMN Column1,
DROP COLUMN Column2;
or like this1:
ALTER TABLE TableName
DROP Column1,
DROP Column2;
1 The word COLUMN is optional and can be omitted, except for RENAME...